#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>
#include <stdlib.h>
int cmp_int(void* e1, void* e2)
{
	return *(int*)e1 - *(int*)e2;
}

int main()
{
	int arr[7] = { 0 };
	while (scanf("%d %d %d %d %d %d %d", &arr[0], &arr[1], &arr[2], &arr[3], &arr[4], &arr[5], &arr[6]) != EOF)
	{
		qsort(arr, 7, sizeof(arr[0]), cmp_int);
		double mark = (double)(arr[1] + arr[2] + arr[3] + arr[4] + arr[5]) / 5.0;
		printf("%.2lf\n", mark);
	}
	return 0;
}